Alpine Power Pack Amp I got this installed yesterday at Best Buy. Outstanding. My thanks to Hawaiikid for his recommendation. This little AMP is $119. They install in minutes and triple your power output. They plug right in. I have an Alpine ida-x303 which is a great unit but all headunits by themselves have minimal power. I have the Alpine 600 SPS speakers and this little amp really improves the sound and boosts power and loudness. Now the 600's really shine. I am 49 and listen to Classic Rock, Classical Music, Jazz and don't need a Sub or expensive amp setup as I am not into boom boom bass. This system is now perfect. I can cruise down the highway with the windows down and turn it up and it will play over any road noise. I highly recommend. Oh yeah they will work with any brand of headunit. If you don't need or want the hassle/expense of wiring up a standard amp this is the way to go. Crutchfield and Best Buy Reviews are like 4.8/5. Everybody loves it. Viper 350HV Another product I highly recommend. It sells for $199 at BB. I like the added security this unit offers me. I remote camp/flyfish and there can be vehicle breakins with ****bags stealing flyrods/camping gear/anything they can get their filthy hands on. A window gets broken and they open a door this alarm sounds. Exactly what I need. Best Buy installed both for me for FREE! Professional installation by this dude Mike who did my headunit and speakers a few months back. These guys are great they are EXPERTS at installation. I highly recommend. They have deals on installation when you buy headunits and speakers together or various products.